Shred the Peak

What are peaks and why are they important?Hourly Electric Demand and Price - August 29, 2018

Peaks occur when the highest level of electricity is consumed in our region within a specific timeframe.

Peak electricity is expensive, affecting power supply costs and in turn, customer bills. Peaks also impact the environment because the more inefficient and environmentally impacting generators are needed in order to meet the high demand for electricity.

When do peaks occur? 

The peaks that impact RMLD's power supply costs occur once per month and once per year. 


Annual Peak

Monthly Peaks

Impact on power supply costs

The annual peak impacts RMLD’s wholesale Capacity costs. The capacity portion of RMLD’s wholesale power supply costs account for what RMLD must pay to ensure sufficient capacity is available to meet RMLD’s highest potential electricity needs. Capacity costs are based on the amount of electricity RMLD’s system uses during the annual peak hour for our region.

Monthly peaks impact RMLD’s wholesale Transmission costs. The transmission portion of RMLD’s wholesale power supply expenses cover the cost of transmission assets (such as high voltage power lines) needed to supply RMLD’s system with power. Transmission costs are based on the amount of electricity RMLD’s system uses during each monthly peak hour for our region. 

When peak(s) typically occur

The annual peak typically occurs on a hot and humid weekday afternoon from June to August between the hours of 2:00 pm and 7:00 pm.

The monthly peak is most likely to occur on the hottest or coldest weekday of the month. In warmer months, peaks typically occur in the afternoon between the hours of 2:00 pm and 7:00 pm. In cooler months, peaks typically occur in the evening between the hours of 5:00 pm and 9:00 pm. Monthly peaks are particularly hard to predict during the mild spring and fall months.

Potential savings if we shred the peak

Based on current rates, RMLD can save approximately $130,000 in future power supply costs for every 1 megawatt (1,000 kW) of reduction during the annual Capacity peak.

Based on current rates, RMLD can save approximately $10,000/month in future power supply costs for every 1 megawatt (1,000 kW) of reduction during each monthly Transmission peak.

Capacity and Transmission charges are reflected in the Purchase Power Capacity & Trans Charge (PPCT) line item of your RMLD bill.

What is the Shred the Peak Program?

Shred the Peak is a voluntary customer program that encourages conservation during peak times to control related costs and keep rates affordable. RMLD issues Shred the Peak alerts to notify customers when a peak is predicted and asks customers to take simple steps to conserve electricity during the predicted peak window. 

Here's how you can participate:


RMLD will email you the day before or day of a predicted peak. Please note, multiple Shred the Peak Alerts will be issued each month to ensure actual peaks are captured.

CLICK HERE to sign up

Shred the Peak Alerts are also posted to our website, shared on Twitter (@ReadingLight), and sent to the local community television stations.

PLEASE NOTE - RMLD is in the process of rolling out its Customer Notification System. Shred the Peak text, phone, and/or email alerts will be available as a future phase of the project. Customers may enroll to receive these and other future notifications now. CLICK HERE to learn more and sign up. 


When possible, take simple steps to conserve electricity during the predicted peak window.

General Conservation Tips:

  • Turn off lights and electronics that aren’t needed
  • Postpone using washers, dryers, dishwashers, and humidifiers/dehumidifiers until after the predicted peak window

In the Summer:

  • Shut off pool pumps during the predicted peak window
  • Raise the temperature setting on your air conditioner by a few degrees (from 68 to 72, for example)
  • Cook dinner on the grill

In the Winter:

  • Limit the use of electric space heaters
  • If you have electric heat, turn it down by decreasing the temperature setting by a few degrees (from 70 to 67, for example)

What else is RMLD doing to Shred the Peak? 

Local Generation

Electricity that is generated within RMLD’s service area helps to Shred the Peak by reducing the amount of electricity that needs to be purchased from the wholesale market during expensive peak times. Local generation includes:

  • Solar Choice Program – RMLD’s community shared solar program consists of two large solar arrays with a capacity to produce approximately 2.7-megawatts of solar power.
  • 2.5-megawatt Distributed Generator (natural gas powered) – In 2017, RMLD installed a Distributed Generator at its North Reading Substation to run during peak times.
  • 5-megawatt Minuteman Battery Energy Storage System – In 2019, installation of a battery storage unit was completed. The unit is co-located with the Distributed Generator at the North Reading Substation and is discharged during peak times.

RMLD also offers its customers rebates for the installation of residential and commercial solar systems.

Time-of-Use Rate

Rather than one standard rate for all hours, time-of-use has two rates: one that is higher than the standard rate during on-peak hours when electricity is in high demand, and one that is lower than the standard rate during off-peak hours when electricity is not as in demand. Because a different type of meter is required for the time-of-use rate, the customer charge is slightly higher and customers are asked to stay on the rate for a minimum of one year. Time-of-Use is available to residential, commercial, and industrial customers.  

On-peak hours are Monday through Friday from 12:00pm to 7:00pm, excluding holidays. Off-peak hours include weekends, holidays, and all other hours not considered on-peak.

Click here for more info on the residential Time-of-Use Rate.

Customer Programs

In addition to the Shred the Peak program, RMLD has been running a pilot Commercial Peak Demand Reduction Program which incentivizes participating customers to conserve electricity during expensive peak times. This pilot program is limited to RMLD’s largest commercial/industrial customers.

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